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View Full Version : Deburring drill shanks, is there a right way?



airrj
11-29-2010, 09:14 AM
The toolroom that I am working in has 100's of drill bits and there are many, if not most, of them that have burred up shanks. They are still useable as is for work in the shop or field, but it would be nice to clean up some of the worst ones. Also, it makes it harder to chuck them up in the Darex sharpener.

Can anyone suggest an effective way to deburr them without going overboard? I have seen them cleaned up on a belt sander before, but it is very easy to get carried away with that.

Thanks for the help.
R.J.

Mcgyver
11-29-2010, 09:20 AM
I use a fine(ish) file. Try to just hit the burr and with the last few strokes follow the curve of the drill shank. I think any sort of mechanical device runs the high risk of removing more than you want to

Carld
11-29-2010, 09:21 AM
I chuck the drill part in the lathe and use a fine file to file off the high spots being careful to NOT cut the real taper. It takes some practice to do it right but it works just fine. Try to find a dull file to do this.

Black_Moons
11-29-2010, 09:56 AM
I just do it by hand with a normal file, or diamond coated file.. Normal file works because the shanks are typicaly not hardened, thats why they burr up in the first place.. (its that, or your chuck)

The only problem with removing the burrs, is then they slip in the drill chuck again untill a nice burr is raised :)
(The burr kinda helps keep the drill from sliping)

gwilson
11-29-2010, 11:04 AM
Filing off by hand is the best way to avoid damaging the shank. I NEVER use diamonds,though,where any loose ones can get into a hole,or other machine component. Once they get in there,there in for good. Soft shanks don't need diamond files.

Paul Alciatore
11-29-2010, 12:47 PM
I find that the burrs are usually in one place and leave a groove partially around the shank with a built up knob at it's end. I have used files and even grinding wheels in the past, but presently I prefer to use a small stone (1/4" diameter) in the Dremel. I hold the drill at a right angle to the Dremel axis and try to hit the built up knob only. You can take it out to below the shank's OD but the remaining, untouched area above and below this small notch will allow chucking it properly. I use a strip of fine (150-220 grit) sandpaper like a shoe polishing rag to remove any remaining roughness. Most drill chucks are not that accurate, but if you are anal about it, you can rotate the drill and sand it in that manner from three or four equally spaced directions to take the same amount off all sides. Hold it with aluminum or wood jaws in the shop vise for this sanding.

This goes very quickly and the worst part is taking the Dremel out and putting it away. Save up several damaged drills to do at once and the process is much more efficient.

MuellerNick
11-29-2010, 12:53 PM
I just grind off the "knob" on the edge of a grinding wheel. I don't make the slightest attempt to get it flush, in fact I grind it deeper.
By chance, I later saw exactly that procedure done by a professional tool grinder.


Nick

dockrat
11-29-2010, 12:56 PM
pretty much the same as Nick here

miker
11-29-2010, 04:17 PM
[The only problem with removing the burrs, is then they slip in the drill chuck again untill a nice burr is raised :)
(The burr kinda helps keep the drill from sliping)[/QUOTE]

Maybe the shaft should be Knurled to begin with!!:)

Rgds

metalmagpie
11-29-2010, 06:31 PM
I just kiss it on the belt sander. Bye bye burr-y.

Lew Hartswick
11-29-2010, 06:47 PM
[The only problem with removing the burrs, is then they slip in the drill chuck again untill a nice burr is raised :)
(The burr kinda helps keep the drill from sliping)
Maybe the shaft should be Knurled to begin with!!:)

Rgds[/quote]
Or just get those bits with the three flats at 120 :-) They WONT
slip.
...Lew...

airrj
11-29-2010, 10:17 PM
Thanks to all for the suggestions. That should make me good and dangerous. :D I give it a try.

R.J.

mochinist
11-29-2010, 10:23 PM
I just grind off the "knob" on the edge of a grinding wheel. I don't make the slightest attempt to get it flush, in fact I grind it deeper.



Nicksame here.

gwilson
11-29-2010, 10:39 PM
WHAT is the point of further defacing your drill by grinding it DEEPER? It isn't going to GROW back taller,like a plant,after you file it flush. I'd NEVER use a grinder. Use a file.

J Tiers
11-30-2010, 12:43 AM
Take a piece of old file, and stone the teeth until they have small flats on them. Now that piece of file will cut only down to a good surface and stop.

You can safely use it to stone off burrs on drills (stroke it lengthwise) or anything where you would rather just cut off the part that sticks up, and stop before cutting into the 'good" material. Just stroke it as long as there is resistance. When you have cut all the burrs off, it will slide free, and you know you are done.

metalmagpie
11-30-2010, 01:57 AM
WHAT is the point of further defacing your drill by grinding it DEEPER? It isn't going to GROW back taller,like a plant,after you file it flush. I'd NEVER use a grinder. Use a file.

It's never going to be round right there anyway. Doesn't matter how you remove the burr. The rest of the shank will still be round. So use a machine and do it quick.

One thing I've learned is to never use a round drill bit on metal if you're drilling with a modern electric drill, i.e. one with a keyless chuck. Those are guaranteed to spin your bit. For those drills (like my 18V DeWalt for example) use one with flats ground at 120.

vpt
11-30-2010, 08:13 AM
I as well just take them to the grinding wheel and knock down the bump. I can't leave the bumps on my drills or they won't fit in the hole in the drill bit case.

jcon
11-30-2010, 09:06 AM
I agree with the ones saying using a flat file. I hold the point end in one hand and wirh the other hand I lay a file flat on the shank, there is enough contact between the fine and shank that with a light pressure the file will only cut the burr. Any time I use anything else I am sorry.

An ounce of prevention is worth a pound of cure. Most chucks have three holes for the key. Try tighten the chuck in all three holes. I did not believe this would help until I tried it. Try it you will like it. Doing this will also help on a self centering lathe chuck.

jcon